“Wow you’re bendy” can mean a lot of things.
Someone who hyperextends in the shoulders would look like they’re bringing the chest down toward the floor in adho mukha svanasana. The correction would be to bring the lower front ribs back in toward the body rather then thrusting them down toward the floor.
Hyper-mobility in the lumber spine will show up in your back-bending practice where most of the arching is concentrated in the low back rather than distributed throughout the spine (and you would go deeper than most people in back bending poses, although not safely). The correction for that would be to lengthen the tailbone, and engage the pelvic floor and other core muscles. We have a teacher at my studio who had hyper-mobility in her lower back and over-did it on backbends (a long time ago) and it caused permanent damage. Now she cannot backbend at all.
Hyper-mobile students need more muscular engagement to protect the joints from over-extension.
I totally encourage you to inquire more from the people running your teacher training program. When I took my YTT 7 years ago, I asked about hyper-extension in the joints, and I was told that it cuts off the flow of energy in the body. Turns out that may be true, but there are some significant physical ramifications as well.